1. Technical Field
The present invention relates to a spectrometer which measures spectral characteristics of incident light.
2. Related Art
An analyzer which measures light characteristics (such as chromaticity and brightness) of incident light for each wavelength range of the light is known (for example, see JP-A-2005-106753).
The analyzer disclosed in JP-A-2005-106753 introduces light emitted from a light source and reflected by a sample into a wavelength variable interference filter, and guides light transmitted through the wavelength variable interference filter toward a photo-diode to receive the transmitted light thereon. Then, the analyzer detects current outputted from the photo-diode to measure the light characteristics. This type of analyzer changes light which can pass through the wavelength variable interference filter through regulation of the wavelength variable interference filter, thereby sequentially switching from received light to light having a desired wavelength and allowing the photo-diode to receive the desired light.
When the light source of the analyzer is constituted by a white light source such as a tungsten lamp which does not have its peak wavelength within the wavelength range of visible light, the light amount in the short wavelength range emitted from the light source decreases. In this case, the light amount in the short wavelength range of the entire range dividable by the wavelength variable interference filter may also decrease. Thus, the light amount in the short wavelength range received by the photo-diode further decreases, which lowers the measurement accuracy of the spectral characteristics in the short wavelength range and thus makes it difficult to perform accurate measurement of the spectral characteristics of the incident light.